/*
 * hostapd / IEEE 802.11 Management: Beacon and Probe Request/Response
 * Copyright (c) 2002-2004, Instant802 Networks, Inc.
 * Copyright (c) 2005-2006, Devicescape Software, Inc.
 * Copyright (c) 2008-2012, Jouni Malinen <j@w1.fi>
 *
 * This software may be distributed under the terms of the BSD license.
 * See README for more details.
 */

#include "utils/includes.h"

#ifndef CONFIG_NATIVE_WINDOWS

#include "utils/common.h"
#include "common/ieee802_11_defs.h"
#include "common/ieee802_11_common.h"
#include "common/hw_features_common.h"
#include "wps/wps_defs.h"
#include "p2p/p2p.h"
#include "ap/hostapd.h"
#include "ieee802_11.h"
#include "wpa_auth.h"
#include "wmm.h"
#include "ap_config.h"
#include "ap/sta_info.h"
#include "p2p_hostapd.h"
#include "ap_drv_ops.h"
#include "beacon.h"
#include "hs20.h"
#include "ap/dfs.h"

#include "include.h"
#include "uart_pub.h"

#ifdef NEED_AP_MLME
static u8 * hostapd_eid_rm_enabled_capab(struct hostapd_data *hapd, u8 *eid,
                     size_t len)
{
    if (!hapd->conf->radio_measurements || len < 2 + 4)
        return eid;

    *eid++ = WLAN_EID_RRM_ENABLED_CAPABILITIES;
    *eid++ = 5;
    *eid++ = (hapd->conf->radio_measurements & BIT(0)) ?
        WLAN_RRM_CAPS_NEIGHBOR_REPORT : 0x00;
    *eid++ = 0x00;
    *eid++ = 0x00;
    *eid++ = 0x00;
    *eid++ = 0x00;
    return eid;
}
static u8 * hostapd_eid_bss_load(struct hostapd_data *hapd, u8 *eid, size_t len)
{
    if (len < 2 + 5)
        return eid;

#ifdef CONFIG_TESTING_OPTIONS
    if (hapd->conf->bss_load_test_set) {
        *eid++ = WLAN_EID_BSS_LOAD;
        *eid++ = 5;
        os_memcpy(eid, hapd->conf->bss_load_test, 5);
        eid += 5;
        return eid;
    }
#endif /* CONFIG_TESTING_OPTIONS */
    if (hapd->conf->bss_load_update_period) {
        *eid++ = WLAN_EID_BSS_LOAD;
        *eid++ = 5;
        WPA_PUT_LE16(eid, hapd->num_sta);
        eid += 2;
        *eid++ = hapd->iface->channel_utilization;
        WPA_PUT_LE16(eid, 0); /* no available admission capabity */
        eid += 2;
    }
    return eid;
}


static u8 ieee802_11_erp_info(struct hostapd_data *hapd)
{
    u8 erp = 0;

    if (hapd->iface->current_mode == NULL ||
        hapd->iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G)
        return 0;

    if (hapd->iface->olbc)
        erp |= ERP_INFO_USE_PROTECTION;
    if (hapd->iface->num_sta_non_erp > 0) {
        erp |= ERP_INFO_NON_ERP_PRESENT |
            ERP_INFO_USE_PROTECTION;
    }
    if (hapd->iface->num_sta_no_short_preamble > 0 ||
        hapd->iconf->preamble == LONG_PREAMBLE)
        erp |= ERP_INFO_BARKER_PREAMBLE_MODE;

    return erp;
}


static u8 * hostapd_eid_ds_params(struct hostapd_data *hapd, u8 *eid)
{
    *eid++ = WLAN_EID_DS_PARAMS;
    *eid++ = 1;
    *eid++ = hapd->iconf->channel;
    return eid;
}


static u8 * hostapd_eid_erp_info(struct hostapd_data *hapd, u8 *eid)
{
    if (hapd->iface->current_mode == NULL ||
        hapd->iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G)
        return eid;

    /* Set NonERP_present and use_protection bits if there
     * are any associated NonERP stations. */
    /* TODO: use_protection bit can be set to zero even if
     * there are NonERP stations present. This optimization
     * might be useful if NonERP stations are "quiet".
     * See 802.11g/D6 E-1 for recommended practice.
     * In addition, Non ERP present might be set, if AP detects Non ERP
     * operation on other APs. */

    /* Add ERP Information element */
    *eid++ = WLAN_EID_ERP_INFO;
    *eid++ = 1;
    *eid++ = ieee802_11_erp_info(hapd);

    return eid;
}


static u8 * hostapd_eid_pwr_constraint(struct hostapd_data *hapd, u8 *eid)
{
    u8 *pos = eid;
    u8 local_pwr_constraint = 0;
    int dfs;

    if (hapd->iface->current_mode == NULL ||
        hapd->iface->current_mode->mode != HOSTAPD_MODE_IEEE80211A)
        return eid;

    /* Let host drivers add this IE if DFS support is offloaded */
    if (hapd->iface->drv_flags & WPA_DRIVER_FLAGS_DFS_OFFLOAD)
        return eid;

    /*
     * There is no DFS support and power constraint was not directly
     * requested by config option.
     */
    if (!hapd->iconf->ieee80211h &&
        hapd->iconf->local_pwr_constraint == -1)
        return eid;

    /* Check if DFS is required by regulatory. */
    dfs = hostapd_is_dfs_required(hapd->iface);
    if (dfs < 0) {
        wpa_printf(MSG_WARNING, "Failed to check if DFS is required; ret=%d",
               dfs);
        dfs = 0;
    }

    if (dfs == 0 && hapd->iconf->local_pwr_constraint == -1)
        return eid;

    /*
     * ieee80211h (DFS) is enabled so Power Constraint element shall
     * be added when running on DFS channel whenever local_pwr_constraint
     * is configured or not. In order to meet regulations when TPC is not
     * implemented using a transmit power that is below the legal maximum
     * (including any mitigation factor) should help. In this case,
     * indicate 3 dB below maximum allowed transmit power.
     */
    if (hapd->iconf->local_pwr_constraint == -1)
        local_pwr_constraint = 3;

    /*
     * A STA that is not an AP shall use a transmit power less than or
     * equal to the local maximum transmit power level for the channel.
     * The local maximum transmit power can be calculated from the formula:
     * local max TX pwr = max TX pwr - local pwr constraint
     * Where max TX pwr is maximum transmit power level specified for
     * channel in Country element and local pwr constraint is specified
     * for channel in this Power Constraint element.
     */

    /* Element ID */
    *pos++ = WLAN_EID_PWR_CONSTRAINT;
    /* Length */
    *pos++ = 1;
    /* Local Power Constraint */
    if (local_pwr_constraint)
        *pos++ = local_pwr_constraint;
    else
        *pos++ = hapd->iconf->local_pwr_constraint;

    return pos;
}


static u8 * hostapd_eid_country_add(u8 *pos, u8 *end, int chan_spacing,
                    struct hostapd_channel_data *start,
                    struct hostapd_channel_data *prev)
{
    if (end - pos < 3)
        return pos;

    /* first channel number */
    *pos++ = start->chan;
    /* number of channels */
    *pos++ = (prev->chan - start->chan) / chan_spacing + 1;
    /* maximum transmit power level */
    *pos++ = start->max_tx_power;

    return pos;
}


static u8 * hostapd_eid_country(struct hostapd_data *hapd, u8 *eid,
                int max_len)
{
    u8 *pos = eid;
    u8 *end = eid + max_len;
    int i;
    struct hostapd_hw_modes *mode;
    struct hostapd_channel_data *start, *prev;
    int chan_spacing = 1;

    if (!hapd->iconf->ieee80211d || max_len < 6 ||
        hapd->iface->current_mode == NULL)
        return eid;

    *pos++ = WLAN_EID_COUNTRY;
    pos++; /* length will be set later */
    os_memcpy(pos, hapd->iconf->country, 3); /* e.g., 'US ' */
    pos += 3;

    mode = hapd->iface->current_mode;
    if (mode->mode == HOSTAPD_MODE_IEEE80211A)
        chan_spacing = 4;

    start = prev = NULL;
    for (i = 0; i < mode->num_channels; i++) {
        struct hostapd_channel_data *chan = &mode->channels[i];
        if (chan->flag & HOSTAPD_CHAN_DISABLED)
            continue;
        if (start && prev &&
            prev->chan + chan_spacing == chan->chan &&
            start->max_tx_power == chan->max_tx_power) {
            prev = chan;
            continue; /* can use same entry */
        }

        if (start && prev) {
            pos = hostapd_eid_country_add(pos, end, chan_spacing,
                              start, prev);
            start = NULL;
        }

        /* Start new group */
        start = prev = chan;
    }

    if (start) {
        pos = hostapd_eid_country_add(pos, end, chan_spacing,
                          start, prev);
    }

    if ((pos - eid) & 1) {
        if (end - pos < 1)
            return eid;
        *pos++ = 0; /* pad for 16-bit alignment */
    }

    eid[1] = (pos - eid) - 2;

    return pos;
}


static u8 * hostapd_eid_wpa(struct hostapd_data *hapd, u8 *eid, size_t len)
{
    const u8 *ie;
    size_t ielen;

    ie = wpa_auth_get_wpa_ie(hapd->wpa_auth, &ielen);
    if (ie == NULL || ielen > len)
        return eid;

    os_memcpy(eid, ie, ielen);
    return eid + ielen;
}


static u8 * hostapd_eid_csa(struct hostapd_data *hapd, u8 *eid)
{
    u8 chan;

    if (!hapd->cs_freq_params.freq)
        return eid;

    if (ieee80211_freq_to_chan(hapd->cs_freq_params.freq, &chan) ==
        NUM_HOSTAPD_MODES)
        return eid;

    *eid++ = WLAN_EID_CHANNEL_SWITCH;
    *eid++ = 3;
    *eid++ = hapd->cs_block_tx;
    *eid++ = chan;
    *eid++ = hapd->cs_count;

    return eid;
}


static u8 * hostapd_eid_secondary_channel(struct hostapd_data *hapd, u8 *eid)
{
    u8 sec_ch;

    if (!hapd->cs_freq_params.sec_channel_offset)
        return eid;

    if (hapd->cs_freq_params.sec_channel_offset == -1)
        sec_ch = HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW;
    else if (hapd->cs_freq_params.sec_channel_offset == 1)
        sec_ch = HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE;
    else
        return eid;

    *eid++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
    *eid++ = 1;
    *eid++ = sec_ch;

    return eid;
}


static u8 * hostapd_add_csa_elems(struct hostapd_data *hapd, u8 *pos,
                  u8 *start, unsigned int *csa_counter_off)
{
    u8 *old_pos = pos;

    if (!csa_counter_off)
        return pos;

    *csa_counter_off = 0;
    pos = hostapd_eid_csa(hapd, pos);

    if (pos != old_pos) {
        /* save an offset to the counter - should be last byte */
        *csa_counter_off = pos - start - 1;
        pos = hostapd_eid_secondary_channel(hapd, pos);
    }

    return pos;
}


static u8 * hostapd_gen_probe_resp(struct hostapd_data *hapd,
                   const struct ieee80211_mgmt *req,
                   int is_p2p, size_t *resp_len)
{
    struct ieee80211_mgmt *resp;
    u8 *pos, *epos;
    size_t buflen;

#define MAX_PROBERESP_LEN 768
    buflen = MAX_PROBERESP_LEN;
#ifdef CONFIG_WPS
    if (hapd->wps_probe_resp_ie)
        buflen += wpabuf_len(hapd->wps_probe_resp_ie);
#endif /* CONFIG_WPS */
#ifdef CONFIG_P2P
    if (hapd->p2p_probe_resp_ie)
        buflen += wpabuf_len(hapd->p2p_probe_resp_ie);
#endif /* CONFIG_P2P */
#ifdef CONFIG_FST
    if (hapd->iface->fst_ies)
        buflen += wpabuf_len(hapd->iface->fst_ies);
#endif /* CONFIG_FST */
    if (hapd->conf->vendor_elements)
        buflen += wpabuf_len(hapd->conf->vendor_elements);
    if (hapd->conf->vendor_vht) {
        buflen += 5 + 2 + sizeof(struct ieee80211_vht_capabilities) +
            2 + sizeof(struct ieee80211_vht_operation);
    }
    resp = os_zalloc(buflen);
    if (resp == NULL)
        return NULL;

    epos = ((u8 *) resp) + MAX_PROBERESP_LEN;

    resp->frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
                       WLAN_FC_STYPE_PROBE_RESP);
    if (req)
        os_memcpy(resp->da, req->sa, ETH_ALEN);
    os_memcpy(resp->sa, hapd->own_addr, ETH_ALEN);

    os_memcpy(resp->bssid, hapd->own_addr, ETH_ALEN);
    resp->u.probe_resp.beacon_int =
        host_to_le16(hapd->iconf->beacon_int);

    /* hardware or low-level driver will setup seq_ctrl and timestamp */
    resp->u.probe_resp.capab_info =
        host_to_le16(hostapd_own_capab_info(hapd));

    pos = resp->u.probe_resp.variable;
    *pos++ = WLAN_EID_SSID;
    *pos++ = hapd->conf->ssid.ssid_len;
    os_memcpy(pos, hapd->conf->ssid.ssid, hapd->conf->ssid.ssid_len);
    pos += hapd->conf->ssid.ssid_len;

    /* Supported rates */
    pos = hostapd_eid_supp_rates(hapd, pos);

    /* DS Params */
    pos = hostapd_eid_ds_params(hapd, pos);

    pos = hostapd_eid_country(hapd, pos, epos - pos);

    /* Power Constraint element */
    pos = hostapd_eid_pwr_constraint(hapd, pos);

    /* ERP Information element */
    pos = hostapd_eid_erp_info(hapd, pos);

    /* Extended supported rates */
    pos = hostapd_eid_ext_supp_rates(hapd, pos);

    /* RSN, MDIE, WPA */
    pos = hostapd_eid_wpa(hapd, pos, epos - pos);

    pos = hostapd_eid_bss_load(hapd, pos, epos - pos);

    pos = hostapd_eid_rm_enabled_capab(hapd, pos, epos - pos);

#ifdef CONFIG_IEEE80211N
    pos = hostapd_eid_ht_capabilities(hapd, pos);
    pos = hostapd_eid_ht_operation(hapd, pos);
#endif /* CONFIG_IEEE80211N */

    pos = hostapd_eid_ext_capab(hapd, pos);

    pos = hostapd_eid_time_adv(hapd, pos);
    pos = hostapd_eid_time_zone(hapd, pos);

    pos = hostapd_eid_interworking(hapd, pos);
    pos = hostapd_eid_adv_proto(hapd, pos);
    pos = hostapd_eid_roaming_consortium(hapd, pos);

    pos = hostapd_add_csa_elems(hapd, pos, (u8 *)resp,
                    &hapd->cs_c_off_proberesp);

#ifdef CONFIG_FST
    if (hapd->iface->fst_ies) {
        os_memcpy(pos, wpabuf_head(hapd->iface->fst_ies),
              wpabuf_len(hapd->iface->fst_ies));
        pos += wpabuf_len(hapd->iface->fst_ies);
    }
#endif /* CONFIG_FST */

#ifdef CONFIG_IEEE80211AC
    if (hapd->iconf->ieee80211ac && !hapd->conf->disable_11ac) {
        pos = hostapd_eid_vht_capabilities(hapd, pos);
        pos = hostapd_eid_vht_operation(hapd, pos);
    }
    if (hapd->conf->vendor_vht)
        pos = hostapd_eid_vendor_vht(hapd, pos);
#endif /* CONFIG_IEEE80211AC */

    /* Wi-Fi Alliance WMM */
    pos = hostapd_eid_wmm(hapd, pos);

#ifdef CONFIG_WPS
    if (hapd->conf->wps_state && hapd->wps_probe_resp_ie) {
        os_memcpy(pos, wpabuf_head(hapd->wps_probe_resp_ie),
              wpabuf_len(hapd->wps_probe_resp_ie));
        pos += wpabuf_len(hapd->wps_probe_resp_ie);
    }
#endif /* CONFIG_WPS */

#ifdef CONFIG_P2P
    if ((hapd->conf->p2p & P2P_ENABLED) && is_p2p &&
        hapd->p2p_probe_resp_ie) {
        os_memcpy(pos, wpabuf_head(hapd->p2p_probe_resp_ie),
              wpabuf_len(hapd->p2p_probe_resp_ie));
        pos += wpabuf_len(hapd->p2p_probe_resp_ie);
    }
#endif /* CONFIG_P2P */
#ifdef CONFIG_P2P_MANAGER
    if ((hapd->conf->p2p & (P2P_MANAGE | P2P_ENABLED | P2P_GROUP_OWNER)) ==
        P2P_MANAGE)
        pos = hostapd_eid_p2p_manage(hapd, pos);
#endif /* CONFIG_P2P_MANAGER */

#ifdef CONFIG_HS20
    pos = hostapd_eid_hs20_indication(hapd, pos);
    pos = hostapd_eid_osen(hapd, pos);
#endif /* CONFIG_HS20 */

    if (hapd->conf->vendor_elements) {
        os_memcpy(pos, wpabuf_head(hapd->conf->vendor_elements),
              wpabuf_len(hapd->conf->vendor_elements));
        pos += wpabuf_len(hapd->conf->vendor_elements);
    }

    *resp_len = pos - (u8 *) resp;
    return (u8 *) resp;
}


enum ssid_match_result {
    NO_SSID_MATCH,
    EXACT_SSID_MATCH,
    WILDCARD_SSID_MATCH
};

static enum ssid_match_result ssid_match(struct hostapd_data *hapd,
                     const u8 *ssid, size_t ssid_len,
                     const u8 *ssid_list,
                     size_t ssid_list_len)
{
    const u8 *pos, *end;
    int wildcard = 0;

    if (ssid_len == 0)
        wildcard = 1;
    if (ssid_len == hapd->conf->ssid.ssid_len &&
        os_memcmp(ssid, hapd->conf->ssid.ssid, ssid_len) == 0)
        return EXACT_SSID_MATCH;

    if (ssid_list == NULL)
        return wildcard ? WILDCARD_SSID_MATCH : NO_SSID_MATCH;

    pos = ssid_list;
    end = ssid_list + ssid_list_len;
    while (pos + 1 <= end) {
        if (pos + 2 + pos[1] > end)
            break;
        if (pos[1] == 0)
            wildcard = 1;
        if (pos[1] == hapd->conf->ssid.ssid_len &&
            os_memcmp(pos + 2, hapd->conf->ssid.ssid, pos[1]) == 0)
            return EXACT_SSID_MATCH;
        pos += 2 + pos[1];
    }

    return wildcard ? WILDCARD_SSID_MATCH : NO_SSID_MATCH;
}


void sta_track_expire(struct hostapd_iface *iface, int force)
{
    struct os_reltime now;
    struct hostapd_sta_info *info;

    if (!iface->num_sta_seen)
        return;

    os_get_reltime(&now);
    while (0 != (info = dl_list_first(&iface->sta_seen, struct hostapd_sta_info,
                     list))) {
        if (!force &&
            !os_reltime_expired(&now, &info->last_seen,
                    iface->conf->track_sta_max_age))
            break;
        force = 0;

        wpa_printf(MSG_MSGDUMP, "%s: Expire STA tracking entry for "
               MACSTR, iface->bss[0]->conf->iface,
               MAC2STR(info->addr));
        dl_list_del(&info->list);
        iface->num_sta_seen--;
        os_free(info);
    }
}


static struct hostapd_sta_info * sta_track_get(struct hostapd_iface *iface,
                           const u8 *addr)
{
    struct hostapd_sta_info *info;

    dl_list_for_each(info, &iface->sta_seen, struct hostapd_sta_info, list)
        if (os_memcmp(addr, info->addr, ETH_ALEN) == 0)
            return info;

    return NULL;
}


void sta_track_add(struct hostapd_iface *iface, const u8 *addr)
{
    struct hostapd_sta_info *info;

    info = sta_track_get(iface, addr);
    if (info) {
        /* Move the most recent entry to the end of the list */
        dl_list_del(&info->list);
        dl_list_add_tail(&iface->sta_seen, &info->list);
        os_get_reltime(&info->last_seen);
        return;
    }

    /* Add a new entry */
    info = os_zalloc(sizeof(*info));
    os_memcpy(info->addr, addr, ETH_ALEN);
    os_get_reltime(&info->last_seen);

    if (iface->num_sta_seen >= iface->conf->track_sta_max_num) {
        /* Expire oldest entry to make room for a new one */
        sta_track_expire(iface, 1);
    }

    wpa_printf(MSG_MSGDUMP, "%s: Add STA tracking entry for "
           MACSTR, iface->bss[0]->conf->iface, MAC2STR(addr));
    dl_list_add_tail(&iface->sta_seen, &info->list);
    iface->num_sta_seen++;
}


struct hostapd_data *
sta_track_seen_on(struct hostapd_iface *iface, const u8 *addr,
          const char *ifname)
{
    struct hapd_interfaces *interfaces = iface->interfaces;
    size_t i, j;

    for (i = 0; i < interfaces->count; i++) {
        struct hostapd_data *hapd = NULL;

        iface = interfaces->iface[i];
        for (j = 0; j < iface->num_bss; j++) {
            hapd = iface->bss[j];
            if (os_strcmp(ifname, hapd->conf->iface) == 0)
                break;
            hapd = NULL;
        }

        if (hapd && sta_track_get(iface, addr))
            return hapd;
    }

    return NULL;
}


void handle_probe_req(struct hostapd_data *hapd,
              const struct ieee80211_mgmt *mgmt, size_t len,
              int ssi_signal)
{
    u8 *resp;
    struct ieee802_11_elems elems;
    const u8 *ie;
    size_t ie_len;
    size_t i, resp_len;
    int noack;
    enum ssid_match_result res;

    ie = mgmt->u.probe_req.variable;
    if (len < IEEE80211_HDRLEN + sizeof(mgmt->u.probe_req) - VARIABLE_ARRAY_SPARE)
        return;
    if (hapd->iconf->track_sta_max_num)
        sta_track_add(hapd->iface, mgmt->sa);
    ie_len = len - (IEEE80211_HDRLEN + sizeof(mgmt->u.probe_req) - VARIABLE_ARRAY_SPARE);

    for (i = 0; hapd->probereq_cb && i < hapd->num_probereq_cb; i++)
        if (hapd->probereq_cb[i].cb(hapd->probereq_cb[i].ctx,
                        mgmt->sa, mgmt->da, mgmt->bssid,
                        ie, ie_len, ssi_signal) > 0)
            return;

    if (!hapd->iconf->send_probe_response)
        return;

    if (ieee802_11_parse_elems(ie, ie_len, &elems, 0) == ParseFailed) {
        wpa_printf(MSG_DEBUG, "Could not parse ProbeReq from " MACSTR,
               MAC2STR(mgmt->sa));
        return;
    }

    if ((!elems.ssid || !elems.supp_rates)) {
        wpa_printf(MSG_DEBUG, "STA " MACSTR " sent probe request "
               "without SSID or supported rates element",
               MAC2STR(mgmt->sa));
        return;
    }

    if (hapd->conf->ignore_broadcast_ssid && elems.ssid_len == 0 &&
        elems.ssid_list_len == 0) {
        wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR " for "
               "broadcast SSID ignored", MAC2STR(mgmt->sa));
        return;
    }

#ifdef CONFIG_P2P
    if ((hapd->conf->p2p & P2P_GROUP_OWNER) &&
        elems.ssid_len == P2P_WILDCARD_SSID_LEN &&
        os_memcmp(elems.ssid, P2P_WILDCARD_SSID,
              P2P_WILDCARD_SSID_LEN) == 0) {
        /* Process P2P Wildcard SSID like Wildcard SSID */
        elems.ssid_len = 0;
    }
#endif /* CONFIG_P2P */

    res = ssid_match(hapd, elems.ssid, elems.ssid_len,
             elems.ssid_list, elems.ssid_list_len);
    if (res == NO_SSID_MATCH) {
        if (!(mgmt->da[0] & 0x01)) {
            wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR
                   " for foreign SSID '%s' (DA " MACSTR ")%s",
                   MAC2STR(mgmt->sa),
                   wpa_ssid_txt(elems.ssid, elems.ssid_len),
                   MAC2STR(mgmt->da),
                   elems.ssid_list ? " (SSID list)" : "");
        }
        return;
    }

#ifdef CONFIG_INTERWORKING
    if (hapd->conf->interworking &&
        elems.interworking && elems.interworking_len >= 1) {
        u8 ant = elems.interworking[0] & 0x0f;
        if (ant != INTERWORKING_ANT_WILDCARD &&
            ant != hapd->conf->access_network_type) {
            wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR
                   " for mismatching ANT %u ignored",
                   MAC2STR(mgmt->sa), ant);
            return;
        }
    }

    if (hapd->conf->interworking && elems.interworking &&
        (elems.interworking_len == 7 || elems.interworking_len == 9)) {
        const u8 *hessid;
        if (elems.interworking_len == 7)
            hessid = elems.interworking + 1;
        else
            hessid = elems.interworking + 1 + 2;
        if (!is_broadcast_ether_addr(hessid) &&
            os_memcmp(hessid, hapd->conf->hessid, ETH_ALEN) != 0) {
            wpa_printf(MSG_MSGDUMP, "Probe Request from " MACSTR
                   " for mismatching HESSID " MACSTR
                   " ignored",
                   MAC2STR(mgmt->sa), MAC2STR(hessid));
            return;
        }
    }
#endif /* CONFIG_INTERWORKING */

#ifdef CONFIG_P2P
    if ((hapd->conf->p2p & P2P_GROUP_OWNER) &&
        supp_rates_11b_only(&elems)) {
        /* Indicates support for 11b rates only */
        wpa_printf(MSG_EXCESSIVE, "P2P: Ignore Probe Request from "
               MACSTR " with only 802.11b rates",
               MAC2STR(mgmt->sa));
        return;
    }
#endif /* CONFIG_P2P */

    /* TODO: verify that supp_rates contains at least one matching rate
     * with AP configuration */

    if (hapd->conf->no_probe_resp_if_seen_on &&
        is_multicast_ether_addr(mgmt->da) &&
        is_multicast_ether_addr(mgmt->bssid) &&
        sta_track_seen_on(hapd->iface, mgmt->sa,
                  hapd->conf->no_probe_resp_if_seen_on)) {
        wpa_printf(MSG_MSGDUMP, "%s: Ignore Probe Request from " MACSTR
               " since STA has been seen on %s",
               hapd->conf->iface, MAC2STR(mgmt->sa),
               hapd->conf->no_probe_resp_if_seen_on);
        return;
    }

#ifdef CONFIG_TESTING_OPTIONS
    if (hapd->iconf->ignore_probe_probability > 0.0 &&
        drand48() < hapd->iconf->ignore_probe_probability) {
        wpa_printf(MSG_INFO,
               "TESTING: ignoring probe request from " MACSTR,
               MAC2STR(mgmt->sa));
        return;
    }
#endif /* CONFIG_TESTING_OPTIONS */

    resp = hostapd_gen_probe_resp(hapd, mgmt, elems.p2p != NULL,
                      &resp_len);
    if (resp == NULL)
        return;

    /*
     * If this is a broadcast probe request, apply no ack policy to avoid
     * excessive retries.
     */
    noack = !!(res == WILDCARD_SSID_MATCH &&
           is_broadcast_ether_addr(mgmt->da));

    if (hostapd_drv_send_mlme(hapd, resp, resp_len, noack) < 0)
        wpa_printf(MSG_INFO, "handle_probe_req: send failed");

    os_free(resp);

    os_null_printf(MSG_EXCESSIVE, "STA " MACSTR " sent probe request for %s "
           "SSID", MAC2STR(mgmt->sa),
           elems.ssid_len == 0 ? "broadcast" : "our");
}


static u8 * hostapd_probe_resp_offloads(struct hostapd_data *hapd,
                    size_t *resp_len)
{
    /* check probe response offloading caps and print warnings */
    if (!(hapd->iface->drv_flags & WPA_DRIVER_FLAGS_PROBE_RESP_OFFLOAD))
        return NULL;

#ifdef CONFIG_WPS
    if (hapd->conf->wps_state && hapd->wps_probe_resp_ie &&
        (!(hapd->iface->probe_resp_offloads &
           (WPA_DRIVER_PROBE_RESP_OFFLOAD_WPS |
        WPA_DRIVER_PROBE_RESP_OFFLOAD_WPS2))))
        wpa_printf(MSG_WARNING, "Device is trying to offload WPS "
               "Probe Response while not supporting this");
#endif /* CONFIG_WPS */

#ifdef CONFIG_P2P
    if ((hapd->conf->p2p & P2P_ENABLED) && hapd->p2p_probe_resp_ie &&
        !(hapd->iface->probe_resp_offloads &
          WPA_DRIVER_PROBE_RESP_OFFLOAD_P2P))
        wpa_printf(MSG_WARNING, "Device is trying to offload P2P "
               "Probe Response while not supporting this");
#endif  /* CONFIG_P2P */

    if (hapd->conf->interworking &&
        !(hapd->iface->probe_resp_offloads &
          WPA_DRIVER_PROBE_RESP_OFFLOAD_INTERWORKING))
        wpa_printf(MSG_WARNING, "Device is trying to offload "
               "Interworking Probe Response while not supporting "
               "this");

    /* Generate a Probe Response template for the non-P2P case */
    return hostapd_gen_probe_resp(hapd, NULL, 0, resp_len);
}

#endif /* NEED_AP_MLME */


int ieee802_11_build_ap_params(struct hostapd_data *hapd,
                   struct wpa_driver_ap_params *params)
{
    struct ieee80211_mgmt *head = NULL;
    u8 *tail = NULL;
    size_t head_len = 0, tail_len = 0;
    u8 *resp = NULL;
    size_t resp_len = 0;
#ifdef NEED_AP_MLME
    u16 capab_info;
    u8 *pos, *tailpos;

#define BEACON_HEAD_BUF_SIZE 256
#define BEACON_TAIL_BUF_SIZE 512
    head = os_zalloc(BEACON_HEAD_BUF_SIZE);
    tail_len = BEACON_TAIL_BUF_SIZE;

    if (hapd->conf->vendor_elements)
        tail_len += wpabuf_len(hapd->conf->vendor_elements);

#ifdef CONFIG_IEEE80211AC
    if (hapd->conf->vendor_vht) {
        tail_len += 5 + 2 + sizeof(struct ieee80211_vht_capabilities) +
            2 + sizeof(struct ieee80211_vht_operation);
    }
#endif /* CONFIG_IEEE80211AC */

    tailpos = tail = os_malloc(tail_len);
    if (head == NULL || tail == NULL) {
        wpa_printf(MSG_ERROR, "Failed to set beacon data");
        os_free(head);
        os_free(tail);
        return -1;
    }

    head->frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
                       WLAN_FC_STYPE_BEACON);
    head->duration = host_to_le16(0);
    os_memset(head->da, 0xff, ETH_ALEN);

    os_memcpy(head->sa, hapd->own_addr, ETH_ALEN);
    os_memcpy(head->bssid, hapd->own_addr, ETH_ALEN);
    head->u.beacon.beacon_int =
        host_to_le16(hapd->iconf->beacon_int);

    /* hardware or low-level driver will setup seq_ctrl and timestamp */
    capab_info = hostapd_own_capab_info(hapd);
    head->u.beacon.capab_info = host_to_le16(capab_info);
    pos = &head->u.beacon.variable[0];

    /* SSID */
    *pos++ = WLAN_EID_SSID;
    if (hapd->conf->ignore_broadcast_ssid == 2) {
        /* clear the data, but keep the correct length of the SSID */
        *pos++ = hapd->conf->ssid.ssid_len;
        os_memset(pos, 0, hapd->conf->ssid.ssid_len);
        pos += hapd->conf->ssid.ssid_len;
    } else if (hapd->conf->ignore_broadcast_ssid) {
        *pos++ = 0; /* empty SSID */
    } else {
        *pos++ = hapd->conf->ssid.ssid_len;
        os_memcpy(pos, hapd->conf->ssid.ssid, hapd->conf->ssid.ssid_len);
        pos += hapd->conf->ssid.ssid_len;
    }

    /* Supported rates */
    pos = hostapd_eid_supp_rates(hapd, pos);

    /* DS Params */
    pos = hostapd_eid_ds_params(hapd, pos);

    head_len = pos - (u8 *) head;

    tailpos = hostapd_eid_country(hapd, tailpos,
                      tail + BEACON_TAIL_BUF_SIZE - tailpos);

    /* Power Constraint element */
    tailpos = hostapd_eid_pwr_constraint(hapd, tailpos);

    /* ERP Information element */
    tailpos = hostapd_eid_erp_info(hapd, tailpos);

    /* Extended supported rates */
    tailpos = hostapd_eid_ext_supp_rates(hapd, tailpos);

    /* RSN, MDIE, WPA */
    tailpos = hostapd_eid_wpa(hapd, tailpos, tail + BEACON_TAIL_BUF_SIZE -
                  tailpos);

    tailpos = hostapd_eid_rm_enabled_capab(hapd, tailpos,
                           tail + BEACON_TAIL_BUF_SIZE -
                           tailpos);

    tailpos = hostapd_eid_bss_load(hapd, tailpos,
                       tail + BEACON_TAIL_BUF_SIZE - tailpos);

#ifdef CONFIG_IEEE80211N
    tailpos = hostapd_eid_ht_capabilities(hapd, tailpos);
    tailpos = hostapd_eid_ht_operation(hapd, tailpos);
#endif /* CONFIG_IEEE80211N */

    tailpos = hostapd_eid_ext_capab(hapd, tailpos);

    /*
     * TODO: Time Advertisement element should only be included in some
     * DTIM Beacon frames.
     */
    tailpos = hostapd_eid_time_adv(hapd, tailpos);

    tailpos = hostapd_eid_interworking(hapd, tailpos);
    tailpos = hostapd_eid_adv_proto(hapd, tailpos);
    tailpos = hostapd_eid_roaming_consortium(hapd, tailpos);
    tailpos = hostapd_add_csa_elems(hapd, tailpos, tail,
                    &hapd->cs_c_off_beacon);

    /* Wi-Fi Alliance WMM */
    tailpos = hostapd_eid_wmm(hapd, tailpos);

    if (hapd->conf->vendor_elements) {
        os_memcpy(tailpos, wpabuf_head(hapd->conf->vendor_elements),
              wpabuf_len(hapd->conf->vendor_elements));
        tailpos += wpabuf_len(hapd->conf->vendor_elements);
    }

    tail_len = tailpos > tail ? tailpos - tail : 0;

    resp = hostapd_probe_resp_offloads(hapd, &resp_len);
#endif /* NEED_AP_MLME */

    os_memset(params, 0, sizeof(*params));
    params->head = (u8 *) head;
    params->head_len = head_len;
    params->tail = tail;
    params->tail_len = tail_len;
    params->proberesp = resp;
    params->proberesp_len = resp_len;
    params->dtim_period = hapd->conf->dtim_period;
    params->beacon_int = hapd->iconf->beacon_int;
    params->basic_rates = hapd->iface->basic_rates;
    params->ssid = hapd->conf->ssid.ssid;
    params->ssid_len = hapd->conf->ssid.ssid_len;
    if ((hapd->conf->wpa & (WPA_PROTO_WPA | WPA_PROTO_RSN)) ==
        (WPA_PROTO_WPA | WPA_PROTO_RSN))
        params->pairwise_ciphers = hapd->conf->wpa_pairwise |
            hapd->conf->rsn_pairwise;
    else if (hapd->conf->wpa & WPA_PROTO_RSN)
        params->pairwise_ciphers = hapd->conf->rsn_pairwise;
    else if (hapd->conf->wpa & WPA_PROTO_WPA)
        params->pairwise_ciphers = hapd->conf->wpa_pairwise;
    params->group_cipher = hapd->conf->wpa_group;
    params->key_mgmt_suites = hapd->conf->wpa_key_mgmt;
    params->auth_algs = hapd->conf->auth_algs;
    params->wpa_version = hapd->conf->wpa;
    params->privacy = hapd->conf->ssid.wep.keys_set || hapd->conf->wpa ||
        (hapd->conf->ieee802_1x &&
         (hapd->conf->default_wep_key_len ||
          hapd->conf->individual_wep_key_len));
    switch (hapd->conf->ignore_broadcast_ssid) {
    case 0:
        params->hide_ssid = NO_SSID_HIDING;
        break;
    case 1:
        params->hide_ssid = HIDDEN_SSID_ZERO_LEN;
        break;
    case 2:
        params->hide_ssid = HIDDEN_SSID_ZERO_CONTENTS;
        break;
    }
    params->isolate = hapd->conf->isolate;
    params->smps_mode = hapd->iconf->ht_capab & HT_CAP_INFO_SMPS_MASK;
#ifdef NEED_AP_MLME
    params->cts_protect = !!(ieee802_11_erp_info(hapd) &
                ERP_INFO_USE_PROTECTION);
    params->preamble = hapd->iface->num_sta_no_short_preamble == 0 &&
        hapd->iconf->preamble == SHORT_PREAMBLE;
    if (hapd->iface->current_mode &&
        hapd->iface->current_mode->mode == HOSTAPD_MODE_IEEE80211G)
        params->short_slot_time =
            hapd->iface->num_sta_no_short_slot_time > 0 ? 0 : 1;
    else
        params->short_slot_time = -1;
    if (!hapd->iconf->ieee80211n || hapd->conf->disable_11n)
        params->ht_opmode = -1;
    else
        params->ht_opmode = hapd->iface->ht_op_mode;
#endif /* NEED_AP_MLME */
    params->interworking = hapd->conf->interworking;
    if (hapd->conf->interworking &&
        !is_zero_ether_addr(hapd->conf->hessid))
        params->hessid = hapd->conf->hessid;
    params->access_network_type = hapd->conf->access_network_type;
    params->ap_max_inactivity = hapd->conf->ap_max_inactivity;
#ifdef CONFIG_P2P
    params->p2p_go_ctwindow = hapd->iconf->p2p_go_ctwindow;
#endif /* CONFIG_P2P */
#ifdef CONFIG_HS20
    params->disable_dgaf = hapd->conf->disable_dgaf;
    if (hapd->conf->osen) {
        params->privacy = 1;
        params->osen = 1;
    }
#endif /* CONFIG_HS20 */
    return 0;
}


void ieee802_11_free_ap_params(struct wpa_driver_ap_params *params)
{
    os_free(params->tail);
    params->tail = NULL;
    os_free(params->head);
    params->head = NULL;
    os_free(params->proberesp);
    params->proberesp = NULL;
}

int ieee802_11_set_beacon(struct hostapd_data *hapd)
{
    struct wpa_driver_ap_params params;
    struct hostapd_freq_params freq;
    struct hostapd_iface *iface = hapd->iface;
    struct hostapd_config *iconf = iface->conf;
    struct wpabuf *beacon, *proberesp, *assocresp;
    int res, ret = -1;

    if (hapd->csa_in_progress) {
        wpa_printf(MSG_ERROR, "Cannot set beacons during CSA period");
        return -1;
    }

    hapd->beacon_set_done = 1;

    if (ieee802_11_build_ap_params(hapd, &params) < 0)
        return -1;

    if (hostapd_build_ap_extra_ies(hapd, &beacon, &proberesp, &assocresp) <
        0)
        goto fail;

    params.beacon_ies = beacon;
    params.proberesp_ies = proberesp;
    params.assocresp_ies = assocresp;
    params.reenable = hapd->reenable_beacon;
    hapd->reenable_beacon = 0;

    if (iface->current_mode &&
        hostapd_set_freq_params(&freq, iconf->hw_mode, iface->freq,
                    iconf->channel, iconf->ieee80211n,
                    iconf->ieee80211ac,
                    iconf->secondary_channel,
                    iconf->vht_oper_chwidth,
                    iconf->vht_oper_centr_freq_seg0_idx,
                    iconf->vht_oper_centr_freq_seg1_idx,
                    iface->current_mode->vht_capab) == 0)
        params.freq = &freq;

    res = hostapd_drv_set_ap(hapd, &params);
    hostapd_free_ap_extra_ies(hapd, beacon, proberesp, assocresp);
    if (res)
        wpa_printf(MSG_ERROR, "Failed to set beacon parameters");
    else
        ret = 0;
fail:
    ieee802_11_free_ap_params(&params);
    return ret;
}


int ieee802_11_set_beacons(struct hostapd_iface *iface)
{
    size_t i;
    int ret = 0;

    for (i = 0; i < iface->num_bss; i++) {
        if (iface->bss[i]->started &&
            ieee802_11_set_beacon(iface->bss[i]) < 0)
            ret = -1;
    }

    return ret;
}


/* only update beacons if started */
int ieee802_11_update_beacons(struct hostapd_iface *iface)
{
    size_t i;
    int ret = 0;

    for (i = 0; i < iface->num_bss; i++) {
        if (iface->bss[i]->beacon_set_done && iface->bss[i]->started &&
            ieee802_11_set_beacon(iface->bss[i]) < 0)
            ret = -1;
    }

    return ret;
}

#endif /* CONFIG_NATIVE_WINDOWS */
